Acute rejection of an organ, transplanted from one human to another, is an important risk factor for allograft failure. The outcome of acute rejection is, however, difficult to predict.
Currently, observation of histologic features in allograft tissue obtained by core needle biopsy is the best predictor whether an acute rejection will respond to anti-rejection therapy. However, the invasive procedure of allograft biopsy is associated with complications such as bleeding, arteriovenous fistula, and even graft loss. Thus, there is a need for a non-invasive method for determining whether a patient suffering from acute rejection of a transplant organ is at risk of loss of the transplanted organ.